A composite vacuum evaporation coil including a base coil and an overwind coil is characterized by the overwind coil being independent of the power source and being confined to the area of the turns of the base coil. Such a composite coil has improved efficiency and operating life.

A hard-glass halogen gas-filled incandescent capsule with a single-end or a double-end has a tungsten filament with a primary coil extending from the barrel into the legs, and a secondary coil forming the barrel. One of the legs of the tungsten filament of the single-ended capsule extends into a pinch or press seal of the glass envelope to result in passive extinction of the electric arc at end-of-life. The end of the filament leg near the press seal may be connected to and/or supported by a molybdenum lead wire of the capsule that is within the pinch or the press seal via a clamp formed on the molybdenum lead wire. The passive extinction occurs when the electric arc is conducted through the filament extending into the press seal. Reliable extinction of the arc within the capsule is achieved with simplicity in construction and minimal materials. The primary coil is preferably stretched out to assume the diameter of the tungsten wire where it is embedded in a pinch seal. This hastens extinction of the arc at end of life and also simplifies manufacture by eliminating close tolerance requirements in the clamp.

An incandescent lamp containing a coiled filament within a vitreous envelope wherein the filament is supported at at least one point along its coil length by a refractory metal support wire one end of which is welded to a coil and the other end secured to the envelope wall by a glass bead. The support prevents filament sag during lamp operation and is especially useful with double-ended high intensity tungsten-halogen lamps having an elliptically shaped filament chamber with an infrared reflecting and visible light transmitting optical interference coating on the chamber.